In theory, an augmented pipe draws more bypass air flow into the pipe, thus, creating more static thrust. To lose or to gain the thrust, it mainly depends on adjusting the diameter of the pipe at different section of the pipe and exhaust velocity. If you can, try to get a larger diameter pipe so you won't have the pressure built up and choking coming from the acoustic effect of cooling and compressed air leaving the exhaust. Adjust the distance between the mouth and turbine exhaust will also increase or decrease the thrust. As a matter of fact, if you do it right, you will have faster exhaust speed and static thrust. The idea is just like the tuned pipe, although the theory is a bit different. The down side is the weight penalty, but then you don't need to add to much weight in the nose to balance out the weight at the tail cone. Personally I prefer having the turbine in the bay area.

Mike